The Business Process Modeling Notation (BPMN) specification provides a graphical notation for expressing business processes in a Business Process Diagram. The objective of BPMN is to support process management by both technical users and business users by providing a notation that is intuitive to business users yet able to represent complex process semantics.

BPMN is constrained to support only the concepts of business process modeling and other modeling views such as Organizational structures, Functional breakdowns, and Data models are not a part of BPMN.

There are three basic types of models that BPMN is used for

• Private (internal) business processes

These are processes that are internal to a specific organization

• Interface (public/abstract) processes

Represent the interactions between a private business process and another process or participant. Only those activities that are used to communicate outside the private business process are included in the interface process. All other "internal" activities of the private business process are not.

• Collaboration Processes

Depict the interactions between two or more business entities. These interactions are defined as a sequence of activities that represent the messages being sent between the entities involved. Collaboration processes are contained within a Pool and the different participant business roles are shown as Lanes within the Pool.

Types of BPMN Diagrams

• High-level private process activities
• Detailed private business process with interactions to one or more external entities (or "Black Box" processes)
• Detailed private business process
• As-is or To-Be business process
• Two or more detailed private business processes interacting
• Detailed private business process relationship to Interface Process
• Detailed private business process relationship to Collaboration Process
• Two or more detailed private business processes interacting through their Interface Processes
• Two or more detailed private business processes interacting through a Collaboration Process
• Two or more detailed private business processes interacting through their Interface Processes and a Collaboration Process

BPMN and Execution Languages

Business analysts study the way companies work and define business processes with simple flow charts. There is a technical gap between the format of the initial design of business processes and the format of the languages that will execute these business processes. This gap needs to be bridged with a formal mechanism that maps the appropriate visualization of the business processes to an appropriate business process model execution language of those business processes. The BPMN specification provides a mapping between the graphics of the notation to the underlying constructs of execution languages, such as Business Process Execution Language BPEL. It should be noted that this concept is still getting mature as currently tools vendor have been facing real difficulties in doing bi-directional code generation between BPMN-BPEL.

Business Process Diagram Components

The people who design and manage business processes model them using Business Process Diagrams, these show the sequencing, routing, start, and end points of the processes and comprise the following diagram elements

• Event - an occurrence that triggers the business to respond.
• Process - a series of activities that are undertaken in order to achieve a result and has clear starting and stopping points.
• Gateway - used to control how flows interact as they converge and diverge to processes.
• Data Object - provide information about how documents, data, and other objects are used and updated within a Process.
• Participant - a business entity, usually a company, company division, or a customer, which controls or is responsible for a business process. Participants map to Pools and Swim Lanes
• Sequence Flow - show the order that activities will be performed in a Process.
• Message Flow - show the flow of messages between two parties that are prepared to send and receive them.
• Association - used to associate information and artifacts with flow objects.
• Text - allows modelers to provide additional information for the reader of a BPMN diagram.
• Group - provide a mechanism to visually organize activities.

Below is a sample BPMN diagram:

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